The M48T201Y/V are self-contained devices that include a real time clock (RTC), programmable alarms, a watchdog timer, and a square wave output which provides control of up to 512 K x 8 of external low-power static RAM. Access to all RTC functions and the external RAM is the same as conventional bytewide SRAM. The 16 TIMEKEEPER® registers offer year, month, date, day, hour, minute, second, calibration, alarm, century, watchdog, and square wave output data. Externally attached static RAMs are controlled by the M48T201Y/V via the GCON and ECON signals.
The 44-pin, 330 mil SOIC provides sockets with gold plated contacts at both ends for direct connection to a separate SNAPHAT® housing containing the battery and crystal. The unique design allows the SNAPHAT battery package to be mounted on top of the SOIC package after the completion of the surface mount process.
Insertion of the SNAPHAT housing after reflow prevents potential battery damage due to the high temperatures required for device surface-mounting. The SNAPHAT housing is keyed to prevent reverse insertion. The SOIC and battery packages are shipped separately in plastic anti-static tubes or in tape & reel form. For the 44-lead SOIC, the battery/crystal package (e.g. SNAPHAT) part number is M4Txx-BR12SH (see Table 19 on page 33).